Queensland to swelter in long heatwave

Queenslanders are being warned to expect extreme temperatures when a lengthy heatwave hits much of the state.

The mercury is tipped to soar over the weekend before the heatwave peaks next week, and there will be no respite until Friday.

Temperatures will push towards the mid-30s in southeast Queensland as early as Saturday. Inland areas are headed for the mid-40s.

Central and northern Queensland are also expected to swelter, with temperatures in many parts of the state expected to be eight to nine degrees above average.

Vulnerable people, including the elderly and sick, have been urged to make a plan now to keep themselves cool.

"It's particularly important to look out for our seniors during the expected weather headed our way, with heat and humidity a risk to the health of older people," Seniors Minister Coralee O'Rourke said.

"Popping next door with a cool drink for an elderly neighbour not only makes sure they're safe and well, it can also help beat social isolation and better connect seniors to their communities."

Other tips include drinking water, keeping outside activity to a minimum, while those without fans or air-conditioning should visit libraries, shopping centres or the cinemas.

Energy Minister Anthony Lynham assured Queenslanders there will be enough electricity to go round during the high demand, with 2000 megawatts of generation in reserve.

"That reserve capacity alone is more than enough to power one million homes during peak demand," Dr Lynham said.

He said households could keep their power bills down by setting air conditioners to 24 degrees and keeping doors and windows closed.

Brisbane is expected to get to 31C on Friday, before temperatures head steadily north from there. The capital is expecting 34C on Saturday, 35C on Sunday, and a peak of 36C on Monday.

Mid-30s temperatures will continue until at least Thursday.

Those trends will be matched on the Gold and Sunshine coasts, and in central and north Queensland.